KR102118260B1 - Composite magnetic material and coil component using same - Google Patents

Abstract

Provided is a composite magnetic material capable of securing high permeability and excellent withstand voltage performance, and a coil component comprising the composite magnetic material. The composite magnetic material includes a resin and first magnetic body particles formed in the resin, and the first magnetic body particles have a first core including a metal magnetic material, and an insulating film covering the first core, and the first core Is a flat shape having a short axis and a long axis, and the thickness T _L of the first core in the insulating film is smaller than the thickness T _S of the first core in the insulating film. Further, the coil component contains a composite magnetic material in the body.

Description

Composite magnetic material and coil parts using the same{COMPOSITE MAGNETIC MATERIAL AND COIL COMPONENT USING SAME}

The present invention relates to composite magnetic materials and coil parts.

A conventional coil component is coated and formed to surround a coil portion having a conductor pattern for a flat coil provided on a substrate, and a substrate, in Japanese Patent Application Publication No. 2013-201375 (Patent Document 1). The metal magnetic powder-containing resin, the flat or needle-shaped first metal magnetic powder contained in the metal magnetic powder-containing resin, and the metal magnetic powder-containing resin and having an average particle diameter smaller than the average particle diameter of the first metal magnetic powder A coil element comprising a second magnetic metal powder is disclosed. Accordingly, it is considered to increase the permeability.

Japanese Patent Publication No. 2013-201375

However, in the conventional coil parts, with the progress of miniaturization, higher withstand voltage performance is required. As a countermeasure for downsizing, in the flat soft magnetic metal powder having an insulating film, it was made to satisfy higher withstand voltage performance by increasing the thickness of the insulating film. However, it was found that when the thickness of the insulating film was increased, high permeability was not obtained. On the other hand, in the above-mentioned conventional coil element, if high permeability is satisfied and miniaturization is performed, there is a fear that the withstand voltage resistance becomes poor.

Therefore, the subject of this invention is providing the composite magnetic material which has high permeability, and which can ensure excellent withstand voltage performance, and the coil component containing this composite magnetic material.

In order to solve the above problems, the composite magnetic material of the present invention,

And a resin and first magnetic body particles formed in the resin,

The first magnetic body particle has a first core including a metal magnetic material, and an insulating film covering the first core,

The first core is a flat shape having a short axis and a long axis,

The thickness T _L of the first core in the insulating film in the long axis direction is smaller than the thickness T _S of the first core in the insulating film in the short axis direction.

In the first magnetic body particle according to the present invention, the first core has a flat shape having a short axis and a long axis. The first core is covered with an insulating film. The thickness T _L of the first core in the insulating film in the long axis direction is smaller than the thickness T _S of the first core in the insulating film in the short axis direction. Thereby, the high magnetic permeability can be obtained especially in the long axis direction of the first core in the first magnetic body particles.

In addition, since the thickness T _S of the first core in the insulating film can be thickened, excellent withstand voltage performance can be ensured, especially in the shortening direction of the first core in the first magnetic body particles.

For this reason, if it is a composite magnetic material containing the 1st magnetic body particle which concerns on this invention, the high magnetic permeability and securing of excellent withstand voltage performance can be compatible.

In one embodiment of the composite magnetic material, the thickness T _{L in} the long axis direction of the first core in the insulating film is 0 nm or more and 50 nm or less.

If it is the said embodiment, especially in the shortening direction of the 1st core in an insulating film, excellent withstand voltage performance can be ensured, and a high magnetic permeability can be obtained also in the long axis direction of a 1st core.

In one embodiment of the composite magnetic material, the composite magnetic material,

Further comprising the second magnetic body particles,

The second magnetic body particle has a second core,

The second core is a flat shape having a short axis and a long axis,

The length in the long axis direction in the second core is shorter than the length in the long axis direction in the first core, and

The length of the shortening direction in the second core is shorter than the length of the shortening direction in the first core.

According to the above-described embodiment, since the filling rate of the magnetic material in the coil component can be made higher, it is possible to better achieve high permeability and excellent withstand voltage performance. As a result, further miniaturization of the coil component is possible, and high magnetic permeability and excellent withstand voltage performance can be provided.

In one embodiment of the composite magnetic material, the aspect ratio of the second core to the aspect ratio of the first core is 1/4 or more and 1/2 or less.

According to the above-described embodiment, the filling rate of the magnetic body particles can be increased by using magnetic body particles having different aspect ratios. Moreover, the flat magnetic material can be oriented in the same direction, and the magnetic permeability can be made higher.

In one embodiment of the composite magnetic material, the composite magnetic material further includes third magnetic body particles,

The third magnetic body particle has a third core, is spherical,

The average particle diameter in the third core is shorter than the length in the minor axis direction in the first core.

According to the above embodiment, the permeability can be made higher. In addition, since the filling rate of the magnetic material in the coil component can be made higher, it is possible to better ensure high permeability and excellent withstand voltage performance. This enables further miniaturization of the coil component, for example.

In one embodiment of the composite magnetic material, the average particle diameter in the third core is 0.2 times or more and 0.8 times or less of the length of the first magnetic body particle in the short axis direction of the first core.

According to the above-described embodiment, the dispersibility of the flat magnetic particles and spherical magnetic particles can be improved. Thereby, for example, the filling rate of the magnetic material in the coil component can be made higher, and higher permeability and excellent withstand voltage performance can be better secured. Further, it is possible to further reduce the size of the coil component.

In one embodiment of the invention, a coil component is provided,

The coil component includes a body comprising the above-mentioned composite magnetic material,

A coil installed in the body and wound in a spiral shape,

It is provided on the body, and has an external electrode electrically connected to the coil.

According to the above-described embodiment, the body formed of the composite magnetic material can achieve both high permeability and securing excellent withstand voltage performance. Moreover, if it is a body according to the present invention, further miniaturization of the coil component becomes possible while achieving both high permeability and securing excellent withstand voltage performance.

In one embodiment of the present invention, the body has a first magnetic body portion disposed on one side in the axial direction of the coil, and a second magnetic body portion disposed on the other side in the axial direction of the coil,

At least one magnetic body part of the first magnetic body part and the second magnetic body part includes the composite magnetic material,

The first magnetic body particles are arranged such that the long axis of the first core included in the composite magnetic material intersects the axial direction of the coil.

According to the above-described embodiment, a thick portion of the insulating layer of the first magnetic material particles is arranged between the external electrode and the coil, thereby increasing insulation resistance and improving withstand voltage performance. In addition, a thin portion of the insulating film of the first magnetic body particles is arranged in a direction in which the magnetic flux of the coil passes, so that excellent high permeability can be obtained. For this reason, the coil component can secure high permeability and excellent withstand voltage performance. In addition, while miniaturizing the coil components, further miniaturization is possible.

In one embodiment of the present invention, at least a portion of the external electrode,

It is located on the end face in the coil axial direction in the magnetic body part containing the composite magnetic material.

According to the above embodiment, it is possible to further increase the insulation resistance of the external electrode and the coil. Further, the withstand voltage performance can be improved.

In one embodiment of the present invention, the magnetic body part including the composite magnetic material has a plurality of layers stacked in the coil axial direction, and among the plurality of layers, the first magnetic body particles are located in a layer positioned on the most coil side. Included.

According to the above embodiment, it is possible to further increase the insulation resistance of the external electrode and the coil. Further, the withstand voltage performance can be improved. In addition, excellent high permeability can be obtained. For this reason, the coil component can secure high permeability and excellent withstand voltage performance. In addition, while miniaturizing the coil components, further miniaturization is possible.

In one embodiment of the present invention, the sintered body has a third magnetic body portion disposed inside the coil, and the third magnetic body portion includes the composite magnetic material, and the first magnetic body particles included in the composite magnetic material The first magnetic body particles are arranged such that the short axis of the first core in the crosses the axial direction of the coil.

According to the above-described embodiment, the long axes of the first magnetic body particles are arranged along the magnetic flux passing through the inside of the coil, whereby excellent high permeability can be obtained. For this reason, the coil component can be made highly permeable.

In one embodiment of the coil component, the coil is an α winding coil or an edge-wise winding coil.

According to the above embodiment, the coil component can more effectively obtain excellent high permeability by the first magnetic body particles.

According to the composite magnetic material of the present invention, a high magnetic permeability can be obtained, and further, excellent withstand voltage performance can be secured. Moreover, if it is the coil component of this invention, high permeability and excellent withstand voltage performance can be achieved, and further miniaturization of a coil component is possible.

1 is a perspective view showing a first embodiment in a coil part of the present invention.
2 is a schematic perspective perspective view of a coil component.
3 is a schematic cross-sectional view of a coil component.
4 is a schematic cross-sectional view of the first magnetic body particles.
5 is an enlarged schematic view of FIG. 3.
Fig. 6 is an enlarged schematic diagram of a part of the coil component in the second embodiment.
7 is an enlarged schematic view of a part of the coil component in the third embodiment, enlarged.
8 is an enlarged schematic view of a part of the coil component in the fourth embodiment, enlarged.
9 is an enlarged schematic view of a part of the coil component in the fifth embodiment.
10 is an enlarged schematic diagram of an enlarged part of a coil component in the sixth embodiment.
11 is a schematic cross-sectional view of a coil component according to a seventh embodiment.
Fig. 12A is an SEM observation view of the thickness of the insulating film in the minor axis direction of the first magnetic body particles.
Fig. 12B is an SEM observation diagram of the thickness of the insulating film in the long axis direction of the first magnetic body particles.
13 is an SEM observation diagram showing the orientation of the first magnetic body particles contained in the composite magnetic material.

Hereinafter, it demonstrates in more detail based on embodiment which shows this invention.

(First embodiment)

1 is a perspective view showing a first embodiment in a coil part of the present invention. 2 is a schematic perspective perspective view of a coil component. 3 is a schematic cross-sectional view of the coil component in the first embodiment.

1, 2 and 3, the coil component 1 is a body comprising a composite magnetic material comprising a resin 25 and first magnetic body particles 10 formed in the resin 25. (20), a coil (2) installed in the body (20), wound in a spiral shape, and installed in the body (20), the coil (2) and the external electrodes (3a, 3b) electrically connected to the To be equipped.

In the first embodiment, between the upper side of the coil 2 and the external electrodes 3a and 3b, a first magnetic body portion 21 is disposed, and the lower side of the coil 2 and the external electrodes 3a and 3b are provided. The second magnetic body part 22 is disposed between the coil sides in.

Further, the coil component 1 has a third magnetic body portion 23 disposed inside the coil 2, and a fourth magnetic body portion 24 is disposed outside the coil 2. The third magnetic body part 23 and the fourth magnetic body part 24 include a resin 25 and granular powder (not shown). When the magnetic body particles are not included, the third magnetic body part and the fourth magnetic body part are also referred to as nonmagnetic parts.

In addition, the 1st magnetic body particle 10 in drawing is schematically demonstrated for description. In addition, the number and dimensions are appropriately selected depending on the required permeability, withstand voltage performance, and the size of the coil component.

Further, the axis L of the coil 2 means a spiral center line of the coil 2, and end faces of the first magnetic body part 21, the third magnetic body part 23, and the second magnetic body part 22 Exists to cross on.

The external electrode 3a covers the entire left surface of the body 20 and covers a portion of the top, bottom, front, and rear surfaces of the body 20. The external electrode 3b covers the entire right surface of the body 20 and covers a part of the top, bottom, front, and rear surfaces of the body 20.

At least a part of the external electrode is located on the end face in the coil axial direction in the magnetic body part containing the composite magnetic material. When the composite magnetic material is disposed between the external electrode and the coil, it is possible to increase the insulation resistance and improve the withstand voltage performance.

In FIG. 3, the external electrodes 3a and 3b are located on the end faces of the first magnetic body part 21 and the second magnetic body part 22 in the coil axis direction.

In addition, in FIG. 3, the external electrodes 3a and 3b disclose an inverted U-shape, but at least one of the external electrodes may have an L-shape or the like.

In the first embodiment, the body 20 has a first magnetic body part arranged on one side in the axial direction of the coil, and a second magnetic body part arranged on the other side in the axial direction of the coil.

At least one magnetic body part of the first magnetic body part and the second magnetic body part includes a composite magnetic material, and the composite magnetic material includes resin 25 and first magnetic body particles 10 formed in the resin 25. It includes.

In addition, the first magnetic body particles 10 included in the composite magnetic material have a first core 11 and a first insulating film 12 covering the first core 11.

In this embodiment, as shown in FIG. 3, the first magnetic body particles 10 are arranged such that the long axis of the first core intersects the axis L direction of the coil. As a result, the first magnetic body particles 10 are adjacent to each other in a thin portion of the insulating film, so that the magnetic permeability can be increased. In addition, when the external electrode is formed on the axial end face of the coil, a thick portion of the insulating film of the magnetic particle 10 is arranged between the external electrode and the coil, so that the withstand voltage of the coil component can be increased.

Preferably, the magnetic body part including the composite magnetic material has a plurality of layers stacked in the coil axis (L) direction, and among the plurality of layers, the first magnetic body is in a layer positioned on the coil 2 side most. Particles 10 are included. Preferably, the first magnetic body particles 10 are arranged such that the long axis of the first core intersects the axis L direction of the coil.

The insulation resistance of the external electrodes 3a and 3b and the coil can be further increased. Further, the withstand voltage performance can be improved. In addition, excellent high permeability can be obtained. For this reason, the coil component can secure high permeability and excellent withstand voltage performance. In addition, while miniaturizing the coil components, further miniaturization is possible.

Preferably, at least one of the magnetic body part including the composite magnetic material, that is, the first magnetic body part 21 and the second magnetic body part 22 in FIG. 3 are stacked in the coil axis L direction. You may have a layer of.

Among the plurality of layers, the first magnetic body particles 10 may be included in the layer positioned on the most coil 2 side. Thereby, the insulation resistance of the external electrode and the coil 2 can be further improved. Further, the withstand voltage performance can be improved.

In the first embodiment, the first magnetic body particles 10 are disposed in the first magnetic body portion 21 and the second magnetic body portion 22.

Here, FIG. 4 is a schematic cross-sectional view of the first magnetic body particle 10. The first magnetic body particle 10 has a first core 11 including a metal magnetic material, and a first insulating film 12 covering the first core 11. The first core 11 has a flat shape having a short axis A1 and a long axis A2.

In addition, the thickness T _{L in} the long axis A2 direction of the first core 11 in the first insulating film 12 is shortened (of the first core 11 in the first insulating film 12) It is smaller than the thickness T _{S in the} direction A1).

In the first insulating film 12, the thickness of the first core 11 in the long axis A2 direction and the thickness in the short axis A1 direction have such a relationship, so that between the coil and the external electrode, the coil axial direction By arranging the composite magnetic material, the withstand voltage performance in the coil component, that is, the withstand voltage performance between the coil 2 and the external electrodes 3a and 3b can be secured. Further, elongation of abnormality of plating on the surface of the coil component 1 can be suppressed. In addition, shorts between the coils 2 can be suppressed.

5 is an enlarged schematic diagram of FIG. 3 in the first embodiment. The first magnetic body particles 10 are arranged so that the long axis A2 of the first core 11 in the first magnetic body particles 10 intersects the axis L direction of the coil 2.

Preferably, the angle formed between the long axis A2 of the first core 11 and the axis L of the coil 2 in the first magnetic body particle 10 is 90°±10°, for example It is 90°±5°. By arranging the first magnetic body particles 10 in such a relationship, the inductance value is improved.

In this aspect, the first magnetic body portion 21 is disposed between the external electrode 3a and the coil 2, and the first magnetic body portion 21 is directed from the coil 2 side toward the external electrode 3a, It has a 1st magnetic body layer 21a, a 2nd magnetic body layer 21b, and a 3rd magnetic body layer 21c.

Preferably, the first magnetic body particles 10 are included in at least one of the first magnetic body layer 21a, the second magnetic body layer 21b, and the third magnetic body layer 21c.

For example, the first magnetic body layer 21a includes the first magnetic body particles 10. In addition, in 1st Embodiment, the 1st magnetic body particle 10 is also included in the 2nd magnetic body layer 21b and the 3rd magnetic body layer 21c.

According to this embodiment, the insulation resistance of the external electrode 3a and the coil 2 can be further improved, and the withstand voltage performance can be improved. In addition, excellent high permeability can be obtained. For this reason, the coil part can achieve both high permeability and excellent withstand voltage performance, and furthermore, it is possible to further downsize the coil part.

Here, although the interface of each of the magnetic body layers 21a, 21b, 21c is indicated by a broken line, by appropriately selecting the resin contained in each magnetic body layer, the first interface is such that the interface between the magnetic body layers 21a, 21b, 21c does not substantially occur. The magnetic body portion 21 can be formed.

Preferably, each magnetic body layer 21a, 21b, 21c is formed of the same resin composition.

When the first magnetic material layer 21a includes the first magnetic material particles 10, the thickness of the coil 2 in the first magnetic material layer 21a in the axis L direction is the coil 2 and the outside. It is preferable that the thickness is at least 1/3 of the thickness between the electrodes 3a, that is, at least 1/3 of the thickness of the first magnetic body portion 21.

For example, the thickness of the coil 2 in the first magnetic layer 21a in the axial (L) direction is that of the first magnetic body portion 21 disposed between the coil 2 and the external electrode 3a. It is 1/3 to 4/5 of the thickness.

Thereby, the insulation resistance of the external electrode 3a and the coil 2 can be further improved, and the withstand voltage performance can be improved. In addition, excellent high permeability can be obtained.

In addition, in this specification, the number, arrangement, etc. of the magnetic body particles shown in the drawings are simplified to explain the invention, and the form, such as the number and arrangement of magnetic body particles, is limited to those described in these drawings. Does not work.

The components included in the coil component 1 will be described in detail below.

The body 20 includes the composite magnetic material according to the present invention, and the composite magnetic material includes a resin. The resin is not particularly limited, and examples thereof include epoxy resins, phenol resins, polyester resins, polyimide resins, and polyolefin resins.

The 1st magnetic body part 21 and the 2nd magnetic body part 22 may contain the same kind of resin, and may contain different types of resin. It is preferably a homogeneous resin.

Further, the resin included in the third magnetic body portion 23 and the fourth magnetic body portion 24 may be the same resin as the resin contained in at least one of the first magnetic body portion 21 and the second magnetic body portion 22. Or resins of different types. It is preferably a homogeneous resin.

The details of the first core are described below.

It is preferable that the metal magnetic material forming the first core 11 is a soft magnetic metal material. As a soft magnetic metal material, for example, Fe, Fe-Ni alloy, Fe-Si-Al alloy, Fe-Si alloy, Fe-Co alloy, Fe-Cr alloy, Fe-Cr-Al alloy, Fe-Cr-Si And alloys, various Fe-based amorphous alloys, and various Fe-based nanocrystalline alloys.

The first core 11 is a flat shape having a short axis A1 and a long axis A2, and the long axis length of the first core 11 is preferably 30 μm or more and 100 μm or less, for example, 40 μm or more and 90 μm. Is below. When the length of the long axis is such a range, a higher permeability can be obtained. In addition, handling properties as a composite magnetic material, for example, fluidity, strength and the like can be improved.

On the other hand, the length of the minor axis A1 of the first core 11 is preferably 0.12 μm or more and 7 μm or less, and more preferably 0.12 μm or more and 5 μm or less. When the length of the short axis A1 of the first core 11 is such a range, the filling rate of the magnetic material in the coil component can be made higher, so that high magnetic permeability and excellent withstand voltage performance can be better secured. . Thereby, further miniaturization of the power inductor, such as a coil component, is possible.

The first core 11 has an aspect ratio (long axis/short axis). This aspect ratio is 15 or more and 250 or less, for example, 20 or more and 240 or less.

Measurement of the length in the short axis (A1) direction and the length in the long axis (A2) direction of the first core 11 can be performed by a known method. For example, it can be performed by observing the first core 11 at a magnification of 1000 times or more and 50000 times or less using a scanning electron microscope (SEM).

Next, the average length of these observation images can be obtained by image analysis using image analysis software. For example, the length of the short axis (A1) direction in the first core 11 is obtained by obtaining and analyzing images by A-phase group (registered trademark), which is an integrated application of IP-1000PC manufactured by Asahi Kasei Engineering Co., Ltd. And the length in the long axis (A2) direction can be measured. In addition, this measurement is repeated a plurality of times, and the average value (each N=20) is referred to as the length in the short axis A1 direction and the length in the long axis A2 direction in the first core 11.

The thickness T _S of the first core 11 in the minor axis A1 direction of the first insulating film 12 is preferably 50 nm or more and 80 nm or less, for example, 50 nm or more and 70 nm. Is below.

Since the thickness T _S of the first core 11 in the minor axis A1 direction is within such a range, excellent withstand voltage performance in the minor axis A1 direction of the first magnetic body particle 10 in the first magnetic body particle 10 Can be secured.

The thickness T _L of the first core 11 in the long axis A2 direction of the first insulating film 12 is preferably 0 nm or more and 50 nm or less, for example, 0.05 nm or more and 40 nm. Is below. When the thickness T _L of the first insulating film 12 is within such a range, the magnetic permeability µ'can be improved in the long axis direction of the first core 11.

In the present invention, the thickness T _{L in} the long axis A2 direction of the first core 11 in the first insulating film 12 is the first core 11 in the first insulating film 12. It is smaller than the thickness T _{S in} the minor axis A1 direction. That is, in the first insulating film 12, the ratio of the thickness of the insulating film in the direction of the long axis A2 and the thickness of the insulating film in the direction of the minor axis A1 (the thickness of the insulating film in the direction of the long axis A2/the thickness of the insulating film in the direction of the short axis A1) is Less than 1. The ratio of the insulating film thickness of the first insulating film 12 is more preferably 2/3 or less. By such a relationship, it is possible to achieve both higher permeability and excellent withstand voltage performance.

Here, the measurement of the film thickness of the 1st insulating film 12 can be performed, for example, by SEM observation of the cross section processed by resin-embedding the 1st magnetic body particle and performing ion milling. The thickness T _{S in} the minor axis A1 direction of the first core 11 in the first insulating film 12 is measured. About the thickness T _L of the 1st core 11 in the long axis A2 direction, the film thickness of the shortest grade is measured.

The thickness of the first core 11 of the first insulating film 12 in the direction of the minor axis (A1) by performing such a measurement at two locations for ten and the first magnetic body particles is calculated, respectively. T _S ) and the thickness T _{L in} the long axis A2 direction of the first core 11 can be obtained.

Next, a method of forming the first insulating film 12 on the first core 11 will be described.

The method of forming the first insulating film 12 on the first core 11 can be appropriately selected. For example, chemical conversion treatment, a sol-gel method, a mechanochemical method, etc. are mentioned.

Below, the method of manufacturing the 1st magnetic body particle 10 by forming the 1st insulating film 12 on the surface of the 1st core 11 by chemical conversion treatment is illustrated.

The soft magnetic metal powder as the first core 11 is immersed in a phosphate treatment liquid and stirred for 60 minutes or more while maintaining a predetermined temperature, for example, 50°C or more and 60°C or less, to remove the required thickness. 1 An insulating film 12 is formed.

Here, if the predetermined temperature is maintained, the phosphate treatment liquid decreases with time. Thereafter, by increasing the number of rotations of the stirring, the first magnetic body particles are brought into contact with each other, and the insulating film attached in the long axis direction (edge end of the first magnetic body particles) can be effectively scraped off, so that the first insulating film 12 The thickness T _{L in} the long axis A2 direction of the first core 11 can be thinly controlled. The number of revolutions to be changed can be changed according to the required film thickness difference, but it is preferable to increase it by 20 rpm or more.

The first magnetic body particles 10 having the desired thickness of the first magnetic body particles having the first insulating film 12 are taken out and dried.

Note that the first insulating film 12 is not limited to a method of forming from a phosphoric acid-based solution, and a silica-based solution or the like may be used.

Next, a method of manufacturing the composite magnetic material will be described.

The composite magnetic material can be appropriately selected, and may be produced by stirring and mixing the first magnetic body particles 10 with a resin and a solvent to prepare a slurry. The obtained slurry may be molded into a plate shape. Moreover, you may form into a sheet form using a comma coater or the like.

The orientation of the first magnetic body particles 10 contained in the composite magnetic material may be oriented by molding in a magnetic field, or by pressing at a predetermined pressure after molding.

Next, a method of manufacturing the coil component 1 will be described.

The coil component 1 can be produced by the manufacturing method described in JP-A-2015-126200 or JP-A-2017-59592 using, for example, a composite magnetic material obtained as described above. have. In addition, the first magnetic body portion 21 and the second magnetic body portion 22 shown in FIG. 3 include the same type of resin and the first magnetic body particles 10 formed in the resin. Depending on the purpose, the material of the first core 11 in the resin, the first magnetic body particles 10, the thickness of the first insulating film 12, and the like may be changed.

Other configurations can be appropriately designed to satisfy the electrical characteristics required for the coil component, for example, inductance values, DC resistance values, DC superimposition characteristics, and the like.

The coil 2 is made of, for example, a low-resistance metal such as Cu, Ag, or Au. Preferably, by using the Cu plating formed by the semi-additive construction method, it is possible to form a coil with a low resistance and a narrow pitch.

The coil 2 may be a coil formed by printing a paste in a coil pattern, or may be a coil formed by winding a metal wire such as an α winding coil or an edge-wise winding coil, or by patterning the plated film into a coil by a potorilithography method. The formed coil may be used.

The coil 2 is preferably an α winding coil or an edge-wise winding coil. When the coil 2 is such a coil, the coil component 1 can more effectively enjoy excellent high permeability by the first magnetic body particles 10.

The external electrodes 3a and 3b are produced by, for example, producing a base electrode with a conductive paste containing Ag as a main component, and then performing Ni plating and Sn plating on the base electrode in this order. However, the shape and material of the external electrodes 3a, 3b are not limited to this.

The coil component 1 is a common mode choke coil. The coil component 1 is mounted on electronic devices such as personal computers, DVD players, digital cameras, TVs, mobile phones, and car electronics, for example.

(Second embodiment)

Fig. 6 is an enlarged schematic diagram illustrating an arrangement of magnetic body particles by enlarging a part of the coil component in the second embodiment.

In the second embodiment, the first magnetic body portion 21A included in the body 20 includes a resin, first magnetic body particles 10 and second magnetic body particles 13a formed in the resin. Similarly, the same configuration can be applied to the second magnetic body 22 (not shown in FIG. 6).

In the second embodiment, the second magnetic body particles 13a have a second core and no insulating film. In this case, the second magnetic body particles 13a correspond to the second core. The second core in the second magnetic body particles 13a has a short axis B1 and a long axis B2, and is flat.

When the second magnetic body particles 13a do not have an insulating film, the filling rate of the magnetic material in the coil component can be made higher. Thereby, high permeability and excellent withstand voltage performance can be favorably secured. Further, it is possible to further miniaturize, for example, a power inductor such as a coil component, while satisfactorily securing high permeability and excellent withstand voltage performance.

Below, it demonstrates centering on difference from 1st Embodiment. Other configurations are the same as those in the first embodiment, and the same reference numerals as in the first embodiment are given and descriptions thereof are omitted.

In the second embodiment, the first magnetic body portion 21A is formed of a composite magnetic material including a resin, first magnetic body particles 10 formed in the resin, and second magnetic body particles 13a. According to this embodiment, the insulation resistance of the external electrode 3a and the coil 2 can be further improved, and the withstand voltage performance can be improved. In addition, excellent high permeability can be obtained. For this reason, the coil part can achieve both high permeability and excellent withstand voltage performance, and furthermore, it is possible to further downsize the coil part.

In the second embodiment, the first magnetic body layer 21a and the third magnetic body layer 21c are layers including the first magnetic body particles 10. Details of the first magnetic body particles 10 are as described above.

It is preferable that the second magnetic body particles 13a have the same aspect ratio as that of the first core 11 of the first magnetic body particles 10.

Depending on the required electrical characteristics and the like, the first magnetic body part 21 may include a spherical soft magnetic metal powder in addition to the first magnetic body particles 10 and the second magnetic body particles 13a.

Further, the second magnetic body particles 13a may have an insulating film. Also in this embodiment, permeability can be made high.

(Third embodiment)

Fig. 7 is an enlarged schematic diagram illustrating an arrangement of magnetic body particles by enlarging a part of the coil component in the third embodiment. In the third embodiment, the first magnetic body portion 21B included in the body 20 is an embodiment comprising a resin, first magnetic body particles 10 and third magnetic body particles 14a formed in the resin. . Similarly, the second magnetic body portion 22 (not shown in Fig. 7) can have the same configuration.

That is, it is an embodiment in which the flat second magnetic body particles 13a included in the second magnetic body layer 21b in the second embodiment are replaced with spherical third magnetic body particles 14a.

Hereinafter, the difference between the first embodiment and the second embodiment will be mainly described.

Other configurations are the same as those in the first and second embodiments, and the same reference numerals as in the first and second embodiments are given, and descriptions thereof are omitted.

In the third embodiment, the third magnetic body particles 14a are spherical. It is preferable that the 3rd magnetic body particle 14a is a soft magnetic metal powder. Further, if desired, the third magnetic body particles 14a may have an insulating film.

In addition, it is preferable that the first magnetic body particles 10 are included in a layer positioned on the most coil side.

It is preferable that the average particle diameter of the third magnetic body particles 14a is 0.5 times or more and 1 time or less of the length of the minor axis A1 of the first core 11 of the first magnetic body particles 10. When the average particle diameter of the third magnetic body particles 14a is within this range, the adhesion between the first magnetic body particles 10 and the third magnetic body particles 14a can be improved. Thereby, withstand voltage performance can be improved, and excellent high permeability can be obtained. In addition, since the filling rate of the magnetic material in the coil component can be made higher, it is possible to better ensure high permeability and excellent withstand voltage performance. Further, it is possible to further miniaturize power inductors such as coil parts, for example, while ensuring high permeability and excellent withstand voltage performance.

The third magnetic body particles 14a may be a mixture of magnetic body particles having at least two kinds of average particle diameters. In this aspect, the average particle diameter of the core in the plurality of magnetic body particles included in the third magnetic body particle 14a is the length of the long axis A2 of the first core 11 of the first magnetic body particle 10. It is appropriately selected from within a range of 0.2 times or more and 1.2 times or less.

When the average particle diameter of the core in at least two kinds of magnetic body particles included in the third magnetic body particle 14a is within this range, the first magnetic body particle 10 and the third magnetic body particle 14a can be brought into close contact. , The dispersibility of the first magnetic body particles 10 and the third magnetic body particles 14a in the first magnetic body portion 21B can be enhanced. Thereby, for example, the filling rate of the magnetic material in the coil component can be made higher, and both high permeability and excellent withstand voltage performance can be better achieved. While achieving both high permeability and excellent withstand voltage performance, further miniaturization of power inductors such as coil components is possible.

(Fourth embodiment)

Fig. 8 is an enlarged schematic diagram illustrating an arrangement of magnetic body particles by enlarging a part of the coil component in the fourth embodiment. In the fourth embodiment, the first magnetic body portion 21C includes the resin, the first magnetic body particles 10 formed in the resin, the second magnetic body particles 13a, and the third magnetic body particles 14a. to be. Similarly, the same configuration can be applied to the second magnetic body 22 (not shown in FIG. 8).

Below, it demonstrates centering on difference from 1st Embodiment-3rd Embodiment. Other configurations are the same as those in the first to third embodiments, and the same reference numerals as in the first to third embodiments are given, and descriptions thereof are omitted.

In the fourth embodiment, the first magnetic body portion 21C includes a resin, first magnetic body particles 10 formed in the resin, second magnetic body particles 13a, and third magnetic body particles 14a. . According to this embodiment, the insulation resistance of the external electrode 3a and the coil 2 can be further improved, and the withstand voltage performance can be improved. In addition, since the filling rate of the magnetic material can be made higher, excellent high permeability can be obtained. For this reason, the coil part can achieve both high permeability and excellent withstand voltage performance, and furthermore, it is possible to further downsize the coil part.

Preferably, the first magnetic body layer 21a includes the first magnetic body particles 10, the second magnetic body layer 21b includes the second magnetic body particles 13a, and the third magnetic body layer 21c is The third magnetic body particles 14a are included. In addition, the arrangement|positioning of the 2nd magnetic body particle 13a and the 3rd magnetic body particle 14a may be replaced respectively, and also in this case, the said 1st magnetic body particle 10 is contained in the layer located in the most coil side. It is desirable to be.

According to this embodiment, the filling rate of the magnetic material in the coil component can be made higher, and both high permeability and excellent withstand voltage performance can be better achieved. In addition, while achieving high permeability and excellent withstand voltage performance, it is possible to further miniaturize a power inductor such as a coil component.

Details of the shape, material, and size of the first magnetic body particle 10, the second magnetic body particle 13a, and the third magnetic body particle 14a are as described above. At least one of the second magnetic body particles 13a and the third magnetic body particles 14a may have an insulating film.

(Fifth embodiment)

Fig. 9 is an enlarged schematic diagram illustrating an arrangement of magnetic body particles by enlarging a part of the coil component in the fifth embodiment. In the fifth embodiment, the first magnetic body portion 21D is an embodiment including the first magnetic body particles 10 and the second magnetic body particles 13b. Similarly, the same configuration can be applied to the second magnetic body 22 (not shown in FIG. 9).

In the fifth embodiment, the second magnetic body particles 13b have a second core. In addition, when the 2nd magnetic body particle 13b does not have an insulating film, the 2nd magnetic body particle 13b means a 2nd core. The second core in the second magnetic body particles 13b has a short axis B1 and a long axis B2, and is flat. The second magnetic body particles 13b may have an insulating film.

According to this embodiment, the permeability can be made higher.

Further, the length of the second core in the minor axis (B1) direction is shorter than the length of the minor axis (A1) direction in the first core 11, and/or the major axis (B2) direction in the second core. The length of is shorter than the length in the minor axis A1 direction in the first core 11.

Preferably, the length in the minor axis (B1) direction in the second core is shorter than the length in the minor axis (A1) direction in the first core 11, and further, the long axis in the second core The length in the (B2) direction is shorter than the length in the long axis A2 direction in the first core 11. According to this embodiment, the permeability can be made higher.

In addition, the filling rate of the magnetic material in the coil component can be made higher, making it possible to achieve both high permeability and excellent withstand voltage performance. In addition, while achieving both high permeability and excellent withstand voltage performance, further miniaturization of power inductors such as coil components is possible.

Below, it demonstrates centering on difference from 1st Embodiment-4th Embodiment. Other configurations are the same as those in the first to fourth embodiments, and the same reference numerals as in the first to fourth embodiments are given and descriptions thereof are omitted.

Details of the shape, material, size, etc. of the first magnetic body particles 10 are as described above.

The first magnetic body particles 10 are arranged such that the long axis A2 of the first core 11 of the first magnetic body particles 10 intersects the axis L direction of the coil. Further, the second magnetic body particles 13b are arranged such that the long axis B2 of the second core intersects the direction of the axis L of the coil. By having such an arrangement, a thick portion of the insulating film can be arranged between the coil and the external electrode, and the withstand voltage can be increased. Further, the permeability can be made higher.

Preferably, the major axis A2 of the first core 11 of the first magnetic body particle 10 and the major axis B2 of the second core of the second magnetic body particle 13b are approximately parallel.

The first magnetic body particle 10 and the second magnetic body particle 13b have a relationship as described above with respect to the axis L of the coil, so that high permeability can be obtained better.

For example, the second magnetic body particle 13b may have an insulating film to prevent short circuit, and in this aspect, the size of the core of the second magnetic body particle 13b satisfies the above condition. If desired, the first magnetic body portion 21D may include a spherical soft magnetic metal powder in addition to the second magnetic body particles 13b.

Here, in 5th Embodiment, the length of the 2nd magnetic body particle 13b in the direction of the minor axis (B1) in the said 2nd core is the length of the minor axis (A1) direction in the said 1st core (11). Is shorter, and/or the length in the long axis B2 direction of the second core is shorter than the length in the long axis A2 direction of the first core 11.

For example, the length of the second magnetic body particle 13b in the minor axis (B1) direction of the second core is the length of the first magnetic body particle 10 in the minor axis (A1) direction. More than 1/3 of the may be 2/3 or less.

When the second magnetic body particles 13b have such a shape, the magnetic permeability can be further increased. In addition, the dispersibility of the first magnetic body particles 10 and the second magnetic body particles 13b can be enhanced. Thereby, for example, the filling rate of the magnetic material in the coil component can be made higher, and both high permeability and excellent withstand voltage performance can be better achieved. In addition, further miniaturization of power inductors such as coil parts is possible.

Further, for example, the length of the second magnetic body particle 13b in the direction of the long axis B2 of the second core is in the direction of the long axis A2 of the first core 11 of the first magnetic body particle 10. The length may be 1/3 to 2/3. Thereby, for example, the filling rate of the magnetic material in the coil component can be made higher, and both high permeability and excellent withstand voltage performance can be better achieved. In addition, further miniaturization of power inductors such as coil parts is possible.

The length of the second magnetic body particle 13b in the direction of the minor axis (B1) in the second core is shorter than the length of the minor core (A1) in the first core 11, and the second core When the length in the long axis B2 direction in is shorter than the length in the long axis A2 direction in the first core 11, the above technical effect can be obtained more effectively.

Further, the aspect ratio of the second magnetic body particles 13b may be different from that of the first core 11 of the first magnetic body particles 10. By using magnetic body particles having different aspect ratios, the first magnetic body particles 10 and the second magnetic body particles 13b can be oriented in the same direction while increasing the filling rate of the magnetic body particles, thereby improving the magnetic permeability.

The aspect ratio of the second magnetic body particles 13b may be 5 or more and 110 or less. In addition, the aspect ratio of the second core in the second magnetic body particle 13b to the aspect ratio of the first core 11 in the first magnetic body particle 10 (the aspect ratio of the second core) Ratio/the aspect ratio of the first core) is preferably 1/4 or more and 1/2 or less.

By including magnetic body particles having different aspect ratios, the flat magnetic body particles can be oriented in the same direction while increasing the filling rate of the magnetic body particles, thereby improving the magnetic permeability.

Here, in the fifth embodiment, the second magnetic body particles 13b may be a soft magnetic metal powder or may have an insulating film. The insulating film in the second magnetic body particles 13b can take the same form as the first insulating film 12 in the first magnetic body particles 10. Specifically, the core of the second magnetic body particle 13b is a flat shape having a short axis and a long axis, and the thickness T _L2 of the core in the long axis direction of the insulating film of the second magnetic body particle 13b is the insulating film. In, it is smaller than the thickness T _{S2 in} the minor axis direction of the core.

In the insulating film of the second magnetic body particles 13b, the thickness T _S2 of the core of the second magnetic body particles 13b in the minor axis (B1) direction is preferably 50 nm or more and 80 nm or less, for example. For example, it is 50 nm or more and 70 nm or less.

Since the thickness T _S2 of the core of the second magnetic body particle 13b in the minor axis (B1) direction is within such a range, excellent withstand voltage performance is obtained in the minor axis (B1) direction of the core of the second magnetic body particle 13b. Can be secured.

In the insulating film of the second magnetic body particle 13b, the thickness T _{L2 in} the long axis B2 direction of the core is preferably 0 nm or more and 50 nm or less, for example, 0.05 nm or more and 40 nm or less. . In the insulating film, the thickness T _L2 of the core in the long axis B2 direction is within such a range, whereby the magnetic permeability μ'can be improved in the long axis direction of the second magnetic material particles 13b of the second core.

In the insulating film of the second magnetic body particles 13b, the ratio of the insulating film thickness in the long axis (B2) direction/the insulating film thickness in the short axis (B1) direction is less than 1, more preferably 2/3 or less. By such a relationship, it is possible to achieve both higher permeability and excellent withstand voltage performance. However, in the insulating film of the second magnetic body particles 13b, the thickness T _L2 of the core in the long axis B2 direction is smaller than the thickness T _S2 of the core in the insulating film in the short axis B1 direction. .

(Sixth embodiment)

Fig. 10 is an enlarged schematic diagram illustrating an arrangement of magnetic body particles by enlarging a part of the coil component in the sixth embodiment. In the sixth embodiment, the first magnetic body portion 21E is an embodiment including the first magnetic body particles 10 and the third magnetic body particles 14b. Similarly, the same configuration can be applied to the second magnetic body 22 (not shown in FIG. 10).

In the sixth embodiment, the third magnetic body particles 14b have a third core. In addition, in the form in which the third magnetic body particle 14b does not have an insulating film, the third magnetic body particle 14b and the third core have the same significance.

According to this embodiment, the permeability can be made higher.

Below, it demonstrates centering on difference from 1st Embodiment-5th Embodiment. Other configurations are the same as those in the first to fifth embodiments, and the same reference numerals as in the first to fifth embodiments are given and descriptions thereof are omitted.

In the sixth embodiment, details of the shape, material, size, etc. of the first magnetic body particles 10 are as described above.

The 3rd magnetic body particle 14b is spherical, has a 3rd core, and the average particle diameter in a 3rd core is shorter than the length in the minor axis A1 direction in the said 1st core 11.

Thereby, the dispersibility of the 1st magnetic body particle 10 and the spherical 3rd magnetic body particle 14b can be improved. Further, for example, the filling rate of the magnetic material in the coil component can be made higher, and a higher magnetic permeability can be induced. Moreover, excellent withstand voltage performance can be secured. In addition, it is possible to further miniaturize a power inductor such as a coil component while having a high magnetic permeability and securing excellent withstand voltage performance.

It is preferable that the 3rd magnetic body particle 14b is a soft magnetic metal powder. Moreover, it is preferable that the 3rd magnetic body particle 14b has an insulating film in order to prevent a short circuit.

It is preferable that the average particle diameter of the third magnetic body particle 14b is 0.2 times or more and 0.8 times or less of the length of the first magnetic body particle 1 in the minor axis A1 direction of the first core 11.

Thereby, the dispersibility of the 1st magnetic body particle 10 and the spherical 3rd magnetic body particle 14b can be improved, for example, the filling rate of the magnetic material in a coil component can be made higher. In addition, it is possible to better achieve high permeability and excellent withstand voltage performance. In addition, it is possible to further miniaturize a power inductor such as a coil component while securing high permeability and excellent withstand voltage performance.

The third magnetic body particles 14b may be a mixture of magnetic body particles having at least two average particle diameters. For example, magnetic particles having a peak value of at least two average particle diameters within a range of 0.2 times to 0.8 times the length of the first magnetic body particle 10 in the direction of the minor axis A1 of the first core , Included in the third magnetic body particle 14b. By having the average particle diameter of at least two types of magnetic body particles 14c within each of these ranges, the first magnetic body particles 10 and the third magnetic body particles 14b having various average particle diameters can be brought into close contact, and the body 20 The dispersibility of the 1st magnetic body particle 10 and the 3rd magnetic body particle 14b in can be improved. Thereby, for example, the filling rate of the magnetic material in the coil component 1 can be made higher, and both high permeability and excellent withstand voltage performance can be better achieved. Further, further miniaturization of the power inductor such as the coil component 1 is possible.

(7th embodiment)

11 is a schematic cross-sectional view of a coil component in a seventh embodiment.

In the seventh embodiment, in the coil component, the body 20 has a third magnetic body portion 23F arranged inside the coil, and the third magnetic body portion 23F includes the composite magnetic material , The first magnetic body particle 10 such that the minor axis A1 of the first core 11 in the first magnetic body particle 10 included in the composite magnetic material intersects the axis L direction of the coil. ) Is a coil component 1 arranged.

Below, it demonstrates centering on difference from 1st Embodiment. Other configurations are the same as those in the first embodiment, and the same reference numerals as in the first embodiment are given and descriptions thereof are omitted.

In the seventh embodiment, the first magnetic body particles 10 having the form illustrated in FIG. 4 are disposed in the third magnetic body portion 23F.

In addition, as shown in FIG. 11, the first magnetic body particles 10 may be disposed on the fourth magnetic body portion 24F, and in this case, the first core 11 in the first magnetic body particles 10 may also be used. ), the first magnetic body particles 10 may be arranged such that the minor axis A1 intersects the axis L direction of the coil.

Preferably, the angle between the minor axis A1 of the first core and the axis L direction of the coil 2 is 90°±10°, for example, 90°±5°.

Thereby, the insulation resistance of the external electrode and the coil can be further increased. Further, the withstand voltage performance can be improved. In addition, excellent high permeability can be obtained. For this reason, the coil component can secure high permeability and excellent withstand voltage performance. Further, while achieving both of these characteristics, further miniaturization of the coil component is possible.

Further, at least one of the third magnetic body portion 23F and the fourth magnetic body portion 24F may include at least one of the second magnetic body particles and the third magnetic body particles. For example, the filling rate of the magnetic material in the coil component can be made higher. In addition, it is possible to better achieve high permeability and excellent withstand voltage performance.

The 1st magnetic body part 21F and the 2nd magnetic body part 22F contain the said resin at least, If desired, you may contain granular powder (not shown). As the granular powder, known granular powder can be selected within a range that does not impair the technical effect in the present embodiment, and satisfies electrical characteristics (inductance value, DC resistance value, DC overlapping characteristic, etc.) required for the coil component. You can choose appropriately.

(Example)

Next, examples of the first embodiment will be described.

(Preparation of first magnetic particle)

The flat FeSiCr powder was immersed in a phosphate treatment solution, stirred at 55°C for 65 minutes, and subjected to chemical conversion treatment. By this treatment, an insulating film was formed on the surface of the flat soft magnetic metal powder.

In the chemical conversion treatment, in accordance with the required film thickness, by increasing the number of rotations of stirring, the flattened soft magnetic metal powder, that is, the insulating film formed on the core of the first magnetic body particles, has a long axis direction of the core (flat metal powder The insulating film formed of the edge edge of the film was cut off, and the thickness of the insulating film formed in the long axis direction of the core was adjusted.

Next, the obtained flat particles were dried to prepare first magnetic body particles.

The film thickness of the obtained first magnetic body particles was measured as follows.

The first magnetic body particles were resin-embedded and the cross section processed by ion milling was observed by SEM using Hitachi High-Tech SU-8040.

For the following sites, SEM images were obtained at a magnification of 100,000 times, among which the maximum value of the thickness of the insulating film was taken as the thickness of the insulating film at each site. Fig. 12A shows an SEM observation diagram of the thickness of the insulating film in the minor axis direction of the first magnetic body particles. According to this measurement, the thickness of the insulating film in the minor axis direction of the core was 121 nm.

In addition, Fig. 12B shows an SEM observation diagram of the thickness of the insulating film in the long axis direction of the first magnetic body particles. According to this measurement, the thickness of the insulating film in the long axis direction of the core was 37 nm.

By the above method, data of 10 particles x 2 places (n=20) were obtained for the first magnetic body particles, and the average value was taken as the film thickness of the first magnetic body particles. In this embodiment, the thickness of the insulating film in the minor axis direction of the core was 65 nm. The thickness of the insulating film in the long axis direction of the core was 40 nm.

(Preparation of composite magnetic materials)

The first magnetic material particles prepared above are mixed with an epoxy resin and a solvent to prepare a slurry. The slurry is molded into a plate shape. When forming into a plate shape, the orientation of the first magnetic body particles was performed. 13 is an SEM observation diagram showing the orientation of the first magnetic body particles contained in the composite magnetic material. In Fig. 13, the flattened portion displayed in white is the first magnetic body particles.

(Manufacture of coil parts)

The coil part of the aspect shown in the schematic sectional drawing of FIG. 3 was produced in accordance with the manufacturing method of Japanese Patent Publication No. 2015-126200 and Japanese Patent Publication No. 2017-59592.

The composite magnetic material obtained above is included in the first magnetic body portion 21 and the second magnetic body portion 22 in FIG. 3. The magnetic permeability μ'(1 MHz) of the first magnetic body portion 21 and the second magnetic body portion 22 was 45.

The body core portion of the body 20 includes a magnetic material obtained by mixing a spherical Fe-based amorphous alloy powder having an D50 particle diameter of 35 µm and 5 µm, respectively, at a weight ratio of 75:25 with a weight ratio of 75:25. do. The permeability of the core portion of the body was μ'(1 MHz) = 30.

According to the above embodiment, it was possible to achieve both high permeability and excellent withstand voltage performance.

In addition, the present invention is not limited to the above-described embodiment, and the design can be changed without departing from the spirit of the present invention. For example, the feature points of the first to seventh embodiments may be variously combined.

1: Coil parts
2: coil
3a, 3b: external electrodes
10: first magnetic particle
11: first core
12: first insulating film
13a, 13b: second magnetic material particles
14a, 14b: third magnetic particle
20: body
21: first magnetic body part
21a: first magnetic layer
21b: second magnetic layer
21c: third magnetic material layer
22: second magnetic body part
23: third magnetic body part
24: fourth magnetic body part
25: resin

Claims (12)

And a resin and first magnetic body particles formed in the resin,
The first magnetic body particle has a first core including a metal magnetic material, and an insulating film covering the first core,
The first core is a flat shape having a short axis and a long axis,
The composite magnetic material in which the thickness T _L of the first core in the insulating film is smaller than the thickness T _S of the first core in the insulating film. According to claim 1,
The composite magnetic material having a thickness T _L of the first core in the insulating film in the long axis direction of 0 nm or more and 50 nm or less. The method according to claim 1 or 2,
Further comprising the second magnetic body particles,
The second magnetic body particle has a second core,
The second core is a flat shape having a short axis and a long axis,
The length in the long axis direction in the second core is shorter than the length in the long axis direction in the first core, and
The composite magnetic material in which the length in the minor axis direction in the second core is shorter than the length in the minor axis direction in the first core. According to claim 3,
A composite magnetic material having an aspect ratio of the second core to 1/4 to 1/2 of an aspect ratio of the first core. The method according to claim 1 or 2,
Further comprising a third magnetic body particles,
The third magnetic body particle has a third core, is spherical,
The composite magnetic material having an average particle diameter in the third core shorter than a length in a minor axis direction in the first core. The method of claim 5,
The composite magnetic material having an average particle diameter in the third core of 0.2 to 0.8 times the length in the minor axis direction of the first core. A body comprising the composite magnetic material according to claim 1 or 2, and
A coil installed in the body and wound in a spiral shape,
A coil component installed on the body and having an external electrode electrically connected to the coil. The method of claim 7,
The said body has a 1st magnetic body part arrange|positioned at one side in the axial direction of the said coil, and a 2nd magnetic body part arrange|positioned at the other side in the axial direction of the said coil,
At least one magnetic body part of the first magnetic body part and the second magnetic body part includes the composite magnetic material,
A coil component in which first magnetic body particles are arranged such that a long axis of the first core included in the composite magnetic material intersects an axial direction of the coil. The method of claim 8,
At least a portion of the external electrode,
A coil component located on an end face in the coil axial direction in the magnetic body portion containing the composite magnetic material. The method of claim 7,
The magnetic body part including the composite magnetic material has a plurality of layers stacked in the coil axis direction,
Of the plurality of layers, to the layer located on the most coil side,
The coil component containing the first magnetic body particles. The method of claim 7,
The said body has a 3rd magnetic body part arrange|positioned inside the coil,
The third magnetic body portion includes the composite magnetic material,
The coil component in which the first magnetic body particles are arranged such that the short axis of the first core in the first magnetic body particles contained in the composite magnetic material intersects the axial direction of the coil. The method of claim 7,
The coil part, wherein the coil is an α winding coil or an edge-wise winding coil.

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